Unmanned Aerial Vehicles (UAVs) are typically flown based on two different flight modes. The first is a multi-rotor flight mode that uses multiple lifting propellers to hover or take off and land vertically by providing generally vertical thrust. The second is a traditional fixed-wing flight mode that uses a large span aerodynamic lifting surface that uses generally horizontal thrust. The multi-rotor flight mode benefits from being easy to launch and land, but it has poor endurance due in part to higher energy consumption. The fixed-wing flight mode is beneficial due to its endurance as a result of lower energy consumption, but it is more difficult to launch and land. There is a new class of“hybrid” aerodynamic vehicles that blend the two strategies to take advantage of their positive attributes.
One hybrid aerodynamic flight strategy is known as a “tilt-rotor”, where thrusters are able to rotate to accommodate different flight modes. In the first vertical flight mode, the thrusters point upwards providing vertical thrust in order to fly like a multi-rotor. In the second horizontal flight mode, the thrusters point forward to provide horizontal thrust in order to fly like a fixed-wing aircraft. In each flight mode, the tilting action of the thrusters can be further used to enable greater control. For example a thruster in the vertical flight mode can be slightly tilted forward or aft to control forward and backward motions.
UAV tilt-rotor mechanisms are difficult to build because they must be tiltable over a large range of motion, while also being durable, light, and consuming minimal power. Some prior art attempts to overcome this required numerous small parts, making them heavy, increasing cost, increasing manufacturing complexity, increasing potential for failure, and the like. On the other hand, some prior art attempts that focused on being durable failed because of high power consumption. Additionally, some prior approaches also failed due to the high torque loads various components were exposed to resulting in either over-engineered heavy structures or component failure.
Other prior art approaches in the field offer no alternative to utilizing gears and other components to allow for a greater degree of rotation of the servo. In some prior art approaches, a connecting linkage restricts the servo motion to a mere 90 degrees of rotation. In other prior art approaches, an aerial vehicle that separates a load bearing aspect of the vehicle from the servo system became an unfavorable limitation. Further, these added connecting linkage gears and components are prone to fail, break, or stress-out.
Many of these and other shortcomings of the prior art are addressed by the various aspects in the present disclosure.